iguana_ex_python_01_action_functions.py

Go to the documentation of this file.

#!/usr/bin/env python3
 
"""!
@begin_doc_example{python}
@file iguana_ex_python_01_action_functions.py
@brief Python version of `iguana_ex_cpp_01_action_functions.cc` (for more details, see this `.cc` file)
@end_doc_example
@doxygen_off
"""
 
import pyiguana
import sys
 
# include the header files that you need
pyiguana.include(
        'hipo4/reader.h',
        'iguana/algorithms/clas12/EventBuilderFilter/Algorithm.h',
        'iguana/algorithms/clas12/MomentumCorrection/Algorithm.h',
        )
# then import the bound namespaces (must be after including the headers)
from cppyy.gbl import hipo, iguana
# from here the syntax is analogous to the C++ example
 
inFile    = sys.argv[1]      if len(sys.argv)>1 else 'data.hipo'
numEvents = int(sys.argv[2]) if len(sys.argv)>2 else 3
 
reader = hipo.reader(inFile)
banks  = reader.getBanks(["REC::Particle", "RUN::config"]);
 
algo_eventbuilder_filter = iguana.clas12.EventBuilderFilter()
algo_momentum_correction = iguana.clas12.MomentumCorrection()
 
algo_eventbuilder_filter.SetOption('log',   'debug')
algo_momentum_correction.SetOption('log',   'debug')
algo_eventbuilder_filter.SetOption('pids',  [11, 211, -211])
 
algo_eventbuilder_filter.Start()
algo_momentum_correction.Start()
 
iEvent = 0
while(reader.next(banks) and (numEvents==0 or iEvent < numEvents)):
    iEvent += 1
 
    particleBank = banks[0]
    configBank   = banks[1]
    particleBank.show()
 
    for row in particleBank.getRowList():
 
        pid = particleBank.getInt('pid', row)
        if(algo_eventbuilder_filter.Filter(pid)):
 
            sector = 1 # FIXME: get the sector number. The algorithm `clas12::SectorFinder` can do this, however
                       # it requires reading full `hipo::bank` objects, whereas this example is meant to demonstrate
                       # `iguana` usage operating _only_ on bank row elements
 
            p_corrected = algo_momentum_correction.Transform(
                    particleBank.getFloat("px", row),
                    particleBank.getFloat("py", row),
                    particleBank.getFloat("pz", row),
                    sector,
                    pid,
                    configBank.getFloat("torus", 0)
                    )
 
            print(f'Accepted PID {pid}:')
            print(f'  p_old = ({particleBank.getFloat("px", row)}, {particleBank.getFloat("py", row)}, {particleBank.getFloat("pz", row)})')
            print(f'  p_new = ({p_corrected.px}, {p_corrected.py}, {p_corrected.pz})')
 
algo_eventbuilder_filter.Stop()
algo_momentum_correction.Stop()
 
"""!@doxygen_on"""